Over the past few years, advances in network transmission have facilitated an explosive increase in data transmission rate. Now, the most up-to-date system deployed in horizontal cabling is Augmented Category 6 system (Cat 6A). Regarding Cat 6A, it is recommended to install shielded system instead of unshielded since shielded cabling does have outstanding immunity to electromagnetic interference from external sources, so as to provide balanced cabling.
The cable for shielded Cat 6A system has larger conductor and insulation than that for the unshielded Cat 6A system. An impact tool is generally required for punching down the wires of the cables into the jacks for shielded or unshielded systems. It is desirable to provide a shielded jack that features toolless design so that the four twisted-pair of a cable can be readily terminated at one time.
In addition, the standard does require horizontal cable to be solid 23AWG in order to prevent the attenuation. However, in telecommunication room, people sometimes might use stranded 26AWG patch cable with one end terminated with modular plug, with the other end terminated with keystone jack. Hence, it is desirable to have a shielded keystone jack capable of supporting not only solid 23AWG (bigger) cable, but also stranded 26AWG (smaller) cable.
It is well known that the shielded system has better external electromagnetic interference immunity than the unshielded system. There is still room for improvement in prevention of electromagnetic leakage.